Recent research on learning, the work of B. F. Skinner, shows that behavior can be changed by its consequences and that immediate feedback to the learner is much more effective than feedback that is delayed. In the teaching of language or other skills, e.g. reading, writing, etc., feedback usually is delayed and often is not related directly to the skill that needs improvement. For example, reading and writing tests are returned to the student after a long time and following such a complex tangle of events, that it is not clear to the student what exactly he was doing wrong. Sometimes on a reading test a student can achieve a high score by skimming the text or guessing on the multiple choice questions afterwards. In the early grades of school where reading and writing development begins, the average time spent reading with individual help from a teacher who provides direct feedback may average less than twenty seconds per day, from a study by R. Vance Hall at the University of Kansas.